©2018 NEC Display Solutions, Ltd.
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7.8 Configuring the Compute Module to shutdown using shutdown
signal from the display
An example Python script
rpi_shutdown.py
is included with the Python based NEC PD SDK. The
script shows how to monitor GPIO 23 for a high to low transition, and how to use this to gracefully
shutdown the Operating System on the Compute Module before power to the module is removed by the
display. Normally this script should be started when the Operating System starts. This can be
accomplished by adding it to the
/etc/rc.local
file on the system. See the instructions provided in the
sample file for more details.
To enable the Shutdown Signal from the display:
1.
On the NEC display navigate to the
COMPUTE MODULE
menu on the OSD.
2.
Select
SERVICE MENU
.
3.
Confirm that the
SHUTDOWN SIGNAL
is set to
ENABLE
.
If not set, then:
a.
Select
SETTING LOCK
and then select
OFF
.
b.
Enter the passcode. The default is
0 0 0 0
.
c.
Select
SHUTDOWN SIGNAL
and then select
ENABLE
.
4.
Adjust the
POWER SUPPLY OFF DELAY
setting to set the delay between setting the shutdown
signal (GPIO 23 goes low) and power to the Compute Module being turned off by the display.
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